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Intermittent error code 11 Rinnai gas water heater

GPKen Member Posts: 1
My water heater works most of the time but occasionally gives a code 11. I get the impression that opening a faucet rapidly is the solution. Could this be a flow sensor problem? Sometimes if I don't get hot water but turn the faucet off for a few seconds and then turn it on, I get hot water. I don't think this is just impatience because the hot water doesn't flow any sooner than usual (because it is already on the way).


  • Slimpickins
    Slimpickins Member Posts: 339
    You need to check your gas pressures, static and dynamic. The maximum and minimums are on the tech sheet or on left side of cabinet. Also check low fire and high fire manifold pressures and adjust if needed.
    If all that's good, pull the burners and blow out with 120 psi of pressure and make sure orifices are clear.
  • Jack
    Jack Member Posts: 1,047
    You don't list the model. How old is it? Generally, if the unit throws and error code it is seeing flow. If the flow sensor doesn't see flow the unit will not code out or provide hot water. Operation begins with that sensor. Make sure, if someone gets into the burner, ignitor flame sensor area that new gaskets are on hand. While you are ordering those get a new ignitor and flame rod. Clean the inducer fan.